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Tag: air conditioning troubleshooting

Basic Air Conditioning Troubleshooting, A Mesa Home AC Tip Sheet

air conditioning troubleshootingSteps Your Tech May Take When Your Mesa Home AC Fails to Cool Properly

Troubleshooting a Mesa home air conditioning unit often exceeds the technical know-how of the average homeowner. Yet knowing a bit about the process can help you to better understand the reasons behind the A/C troubleshoot steps as performed by your local HVAC service tech. This doesn’t mean that you should annoy the tech with an over-the-shoulder gawking. However, many mechanical professionals tend to take a bit of pride in helping the homeowner better understand the basics of air conditioning troubleshooting.

Different Stages of HVAC Troubleshooting

When a tech arrives on site, they sometimes find a system that is either dead or acting dead. This means the tech will be checking breakers, disconnects, fuses, and other power-related heating and cooling system problems. Yet more often than not, “dead cooling” does not include a dead power source.

In this lesson on basic A/C troubleshooting, we want to focus on a unit that runs but fails to efficiently cool your home. So here are some of the points that your local Mesa air conditioning tech will likely investigate.

Steps That Should Precede the Connection of A/C Gauges

1) Evaporator and Condenser Fans – To cool effectively and consistently, the motors installed in your home A/C system must be rightly designed for the unit. This means the tech needs to check the fans to ensure that they are of the correct horsepower. Also, although it may seem a no-brainer, the testing must also ensure that the fans are set to the specified rpm and that they are turning in the correct direction. Cleanliness and size is also important. So expect the tech to confirm that your blower blades are right-sized, right-pitched, and clean.

Arizona Repair or Replace Air Conditioning Troubleshooting2) Air Flow – To provide persistent and reliable Mesa home cooling, the condenser on your A/C unit must be supplied with normal outside air. This means the tech needs to ensure that no other devices are pumping hot air against the condenser. Checking the condition of the system filters is also part of the preliminary air conditioning troubleshooting process. You may also see the A/C tech investigating the condition of your evaporator supply and return ducting. You don’t want to lose cool air due to leaks in the ducting. Neither do you want the system drawing in warm outside air into the ducts.

3) Cleanliness – We already talked about making sure the blower fans are clean, but the tech will go further. He or she will also investigate and ensure that both the condenser and the evaporator coils are clean and that nothing is blocking the expected rate of airflow.

Connecting the HVAC Testing Gauges

Please note that the gauges and pressure checking tools should not be the first tools called into use. Failing to eliminate fundamental problems ensures that the A/C troubleshooting gauges will return incorrect pressures and temperatures. However, once the tech is ready to connect the gauges, the process should be somewhat as follows:

1) Refrigerant – The HVAC testing gauges are in place. The pressures are equalized, and the unit is switch off. Now the tech verifies that your Mesa home A/C contains the specified level of refrigerant. To perform this test, he or she will take a temperature reading of the evaporator coil. What is he or she looking to see: A reading that matches the chart or the pressure/temperature reading on the low side of the testing gauge.

2) Checking the System Operating Pressures – During this stage of the testing, professional air conditioning technicians run the unit until temperatures drop to near 5 degrees above the spec temperatures of the unit in question. What he or she expects from the gauges:

  • Suction pressure ranging between 35 to 40 degrees below return air
  • Superheat at the compressor within 20-30 degrees
  • 20-35 degree discharge pressure above ambient
  • A 20-30 degree rise in air temperature through the condenser
  • A 15-20 degree drop in air temperature through the evaporator
  • At the outlet of the condenser or the receiver, a 10-15 degree subcooling readout

All Test Well Yet The Mesa home A/C Still Fails To Cool Correctly

By now, the tech has either asked you to “give some space” or he or she has shown you what to look for when reading the HVAC gauges. But now… All checks well yet the system still fails to cool your home.

Check the Capacity – This means the tech will now to investigate the web bulb returns on the air as it enters and leaves the evaporator. There will be some calculations involved. And unless the tech has the memory of an elephant, he or she will pull out an enthalpy conversion table or a pshchrometric chart. What exactly is being tested: How much btu of heat is being absorbed by the evaporator. The tech is making a comparison between the running capacities of your system against the design capacity of your system. This helps the A/C tech determine whether your Mesa home cooling system is sufficient to handle your home. Any system that is operating within reasonable range of the design capacity but still fails to persistently and efficiently cool a given space is just plain too small for the task.

So now that you are up-to-snuff on basic air conditioning troubleshooting, call in your local Mesa home AC service team. Contact American Cooling and Heating today.




  1. Any HVAC service should only be performed by a licensed, fully trained, and competent person and/or company.

  2. The contents in this article reflect accumulated data from various sources. ACH cannot and does not accept any legal responsibility to any person in respect of anything or the consequences of any reader responses, actions or lack of actions associated with reliance upon the whole or any part of this article and its content. All trademarks, logos, and associated content displayed are the property of their respective owners.


Air Conditioning Troubleshooting For Homeowners

Air Conditioning TroubleshootingA Homeowner’s Guide To Troubleshooting A/C Equipment Prior To Calling The Repairman

Sometimes even a reliable HVAC service contract through the very best HVAC maintenance firm fails to prevent the need for a bit of rushed homeowner-handled air conditioning troubleshooting. Facts are simple: A well-serviced home A/C system typically runs without a great deal of unexpected complications.

However… Simple accidents and minor process failures do occasionally demand attention.

When you call a quality well-staffed HVAC service center you expect a rapid and often same day response to your home heating or cooling problems. Yet quick service does not always ensure that you will not lose a few hours of work time, or vacation time, or perhaps miss a baseball game you promised to attend.

Thankfully, some of the basic functional problems associated with your typical ducted split-type home air conditioning system can be corrected in record time by you the homeowner. The following tips are not designed to replace scheduled routine HVAC maintenance and service processes. However, this guide will help you check for a quick solution in a tough home cooling or heating situation.

It’s not about trying to save the cost of calling in an A/C repairman. It’s just about avoiding loss time when the problem could be handled by a bit of basic air conditioning troubleshooting.  

** Note **

The following tips are not all-inclusive. Furthermore, we make no effort to evaluate your knack for performing A/C troubleshooting processes. If you do not understand the steps involved in a given process, call someone better qualified for the job.


5-Step Simple Air Conditioning Troubleshooting

1) HVAC System Not Cooling

  1. Confirm that the thermostat/controller temperature setting reflects your cooling expectations and that the unit is set to cooling rather than heating or off.
  2. Check and if necessary reset the main HVAC breaker in your home circuit breaker box. Also check the breaker that is typically located near to modern A/C condensing and heating units.
  3. Visually confirm that both the indoor air handler and the outdoor condensing units are physically running.
  4. Visually confirm that the outdoor condensing unit is not frozen over with ice.
  5. Disengage the main HVAC breaker at your home circuit breaker box. Wait at least one hour before restarting. This may force the system to reset itself.

2) Limited or Nonexistent System Airflow

  1. Ensure that all air filters used in any of your HVAC system components are clean. Replace if necessary. If your system is under an A/C maintenance contract, report the issue to the service provider. You may need to install a better grade of filter or isolate the cause for excess dust in your home.
  2. Visually examine any external or internal units for signs of water accumulation in, near or own the exterior or indoor coil enclosure. Ice accumulation on the external Air Conditioning condensing unit is easily to spot. On the inside unit, be it in the attic, basement or crawlspace, hand test for an excessively cold exterior surface.

3) Overflow From the Indoor Air Handler Drain Pan

  1. Remove any clogs blocking the exhaust pipe on the drain pan (See illustration). If there are not in the exhaustExhaust on Air Handler Drain Pan pipe, this homeowner-handled air conditioning troubleshooting secession should be promoted to the professionals. In the mean time, protect your floors and attic by turning the system off.

4) Compressor Fails But Fan Runs or Compressor Starts But Fan Fails

  1. If the compressor fails to start, there is not much the average homeowner can do. The problem can relate to a bad compressor or merely a system that is low on refrigerant. To fix, call your local HVAC service center.
  2. If the condenser fan fails to turn but the compressor starts, the problem may reside in the condenser fan motor. This repair is also beyond the scope of the average homeowner. Call in the pros.

5) Great AirFlow But Poor Cooling

  1. Measure the temperature difference between the air leaving the air handler and the air entering the air handler. Modern high efficiency air conditioning systems typically run with a near 15-degree drop. Older units may show as much as 18 to 20 degrees difference.
  2. Temperature drops that are below the norm indicate that your system is low on refrigerant. Call in a local HVAC service tech to correct the problem.
  3. Temperature drops that greatly exceed the door indicate that the system is suffering a problem with the airflow system. Clean or replace the air filter. If that does not resolve the problem, ensure that the evaporator coils are clean. It that too fails to resolve the problem, clean the blower wheel.
  4. Possible causes also include improper system design and/or installation, an incorrectly sized duct system, or simply a failure to perform routine HVAC maintenance.

Additional Help Via The ACH Study Guides Resource Links

The preceding air conditioning troubleshooting tips are geared toward homeowners who are seeking a quick fix for a simple and basic HVAC heating or cooling issue. Perhaps you need greater details and a move advanced air conditioning and heating tips guide. Have no fear. Check out the American Cooling and Heating consumer literature page. It’s under the Tips menu. There you can find ACH links to News, Certification study guides, and various other A/C related consumer literature.



1. Any HVAC service should only be performed by a licensed, fully trained, and competent
person and/or company.
2. The contents in this article reflect accumulated data from various sources. ACH cannot and
does not accept any legal responsibility to any person in respect of anything or the consequences
of any reader responses, actions or lack of actions associated with reliance upon the whole or any
part of this article and its content. All trademarks, logos, and associated content displayed are the
property of their respective owners.


Air Conditioning Troubleshooting In Arizona – Resolving Common AC Problems

Air Conditioning Troubleshooting For The Arizona Home Handyman

Air conditioning troubleshooting can sometimes be very simple, but if your problem dips into the core of HVAC functionality, consider hiring out the task to a licensed Arizona A/C professional. Basic air conditioning repairs are rather inexpensive; and if the problem requires extensive heating and cooling equipment replacement, you won’t waste money on guesswork solutions.

However, the Arizona homArizona Air Conditioning Troubleshootinge handyman can resolve some common heating and cooling problems without need of equipment expertise. You start by recognizing that various HVAC failures often link to the same type of system malfunction. This A/C troubleshooting tip sheet addresses the simplistic side of heating and cooling troubleshooting and repair.

Air Conditioning Troubleshooting of Basic Cold Air Issues

When home A/C systems fail to deliver cold air, Arizona homeowners get excited. This country is no place for faulty air conditioning equipment. So let’s look at the basic problems that can keep your cooling system from delivering cool air. The list is divided into two categories:

  1. Inside the House
  2. AND Outside the House.
TIP! If your home gets hot in the Arizona summer temperatures and you’d like to reduce the demand on your air conditioning equipment,  consider installing an insulated metal roof system. It reflects the heat right back up into the sky, allowing your home to gain less heat on sunny days.

A/C Troubleshooting Inside the House

1) Clogged filter

A clogged air filter is simple to fix, yet remains a common in-home heating and cooling complication. Although most homeowners can easily change the heating and cooling filter system, they often tend to neglect simple filter maintenance. Yet a clogged air conditioning filter chokes the airflow through the condenser fins associated with the inside furnace. When your system cannot “breath,” the coil freezes over. To prevent filter clogging, clean or replace your system filter at least once a month.

If a dirty filter causes your unit to freeze up, replace or clean the filter and then thaw the unit by powering down for several hours or until the ice melts. Tip it. Remember: A/C equipment does not cool the home but rather it removes the heated air from inside the home. When your air conditioning system pulls the steamy Arizona air out of your home, it sifts that air through the coolant-filled condenser fins, resulting in hot air displaced by cold air.

TIP! The best Arizona HVAC contractors provide a number for emergency services that are available to call 24 hours of the day.  Don’t get caught without help during a weekend heatwave.

2. Clogged Condenser Fins

On the slightly more complex side of air conditioning troubleshooting, the inside condenser fins can also become clogged with debris. This is typically due to inadequate care of the filter system, but can also be a direct result of a passing Arizona dust storm and an improperly sealed home. Regardless of the cause, cleaning the condenser fins becomes a necessary repair process. Although some homeowners have been known to use a toothbrush as a cleaning tool, specially designed “fin brushes” will do a better job with less risk of damage to the fins.

3. Low Coolant

Low A/C coolant implies significant equipment problems. To check the coolant level, pickup a set of pressure gauges and measure setting according to the documentation of your unit. However, if you are tempted to do some backdoor buying to recharge your leaky unit, don’t go there. First off: Your air conditioning system is designed as a self-contained cooling system. This means that leaks are not normal. Second, to buy and work with A/C coolant legally, you need an EPA license. So call your local Arizona A/C Repair center. The cost for repairing the leak and recharging the system will vary, but here is a basic price guideline:

  • $ 50 – Typical HVAC home service call* (Often applied to the cost of system repair)
  • $120 – Typical flat-price covering first 3 pounds of coolant*
  • $ 50 – Base price per pound for anything over 3 pounds*

Variable expenses include the time involved for tracking down and repairing the leak as well as the cost of replacement parts. For example: A new evaporator coil can start around $350*, and the repair can get rather expensive. Yet it only takes a few years of yearly freon cap-offs to exceed the price of a permanent repair. So why be uncomfortable when a repair is the best way to handle any form of air conditioning coolant leak?

TIP! If you are buying a new HVAC unit, make sure that the one you choose fits your home. American Cooling and Heating will inspect your home and your duct work before they install a new unit.

4. Condenser Fan Motor

If all else is set correctly, including the inside thermostat, yet the inside unit fails to come on, check the condenser fan motor. Some problems are as simple as loose wires. But even if the wire connections are burned, the average Arizona home handyman can handle the repair.


Air Conditioning Troubleshooting Outside Your Home

1. Lack of Power

Before checking any other possibilities, ensure that power is reaching your outside A/C condensing unit. Start by checking the breakers both at the mains and at the breaker box located adjacent to your outside system. In the event that a breaker is melted, fused or reveals a loose wire, call an electrician. Even if you can replace a breaker on your own, home and personal safety demands that you uncover the cause of the failure.

2. Faulty Contactor

When standing near your outside air conditioning equipment, do you hear a loud buzzing noise. If so, consider replacing the unit contactor. The process is as follows:

  1. Cut power to the system
  2. Remove the cover panel located on the backside of the condensing unit
  3. Restore power and locate, without touching any components, the source of the buzzing noise (Typically the contactor has the appearance of a piston enclosed in a box)
  4. Turn the power back off
  5. Use an Ohm-meter to ensure that the flow of electricity has ceased
  6. Remove the contractor
  7. Mark the wire leads and then disconnect
  8. Install a new contactor
  9. Reconnect the wires
  10. Re-assemble the cover
  11. Restore system power.
TIP! Before hiring any HVAC company to install, maintain or repair your Arizona home unit, ask for evidence of insurance.

3. Outside Condenser Fan

For safety purposes, it might be better if you hire a local A/C service professional to service your outside unit. The process of determining the functionality of your outside condenser fan is beyond the scope of this article. However, assuming that you have the electrical expertise to test the fan, replacement, if necessary, is very simple. Just:

  1. Disable power to the system
  2. Remove the top component of the outside A/C housing
  3. Label the wires attached to the system fan, and then disconnect the fan
  4. Clean the connections
  5. Re-assemble the unit replacing the faulty fan with a new fan f. Restore power.
TIP! For top deals on Arizona air conditioning installation and equipment, contact American Cooling and Heating.  And remember, Air Conditioning Troubleshooting is sometimes simple and sometimes difficult.



* All prices are based upon 2014 industry averages and may vary from region to region.



  1. Maintenance must be performed by an authorized American Cooling and Heating HVAC technician.
  2. The contents in this article reflect accumulated data from various sources. ACH cannot and does not accept any legal responsibility to any person in respect of anything or the consequences of any reader responses, actions or lack of actions associated with reliance upon the whole or any part of this article and its content. All trademarks, logos, and associated content displayed are the property of their respective owners.


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